1. Field of the Invention
This invention relates generally to military warheads, specifically to improving the ability of warheads to survive, i.e., to reach a target. It also relates to video, simulation games, simulated battlefield scenarios, security systems on airplanes, and car accident prevention.
2. Prior Art
A warhead is a projectile that may contain a conventional explosive(s), germs, nuclear bomb(s), propaganda, equipment, nuclear debris, and/or conventional bombs. A warhead may be empty, so that it is serves as a decoy. The warhead may be shaped like any of the following: sphere, cone, barrel, pyramid, helicoids, box, continuous chain, any combinations of these, etc. Its body can be made of light materials, such as cloth, and/or a solid material, such as aluminum, steel, etc. A warhead's size can range from several centimeters to tens of meters and its weight can range from less than kilogram to thousands of kilograms.
Warheads usually travel at a high altitude, such as the exo-atmospheric range (over 30 km high) where there is little or no air, and/or at a lower atmospheric range. It is extremely important that the warhead reach the target without being destroyed during its travel or knocked off course by a kill vehicle, i.e., an intercepting missile and/or by a laser beam. Both warheads and kill vehicles can be launched from a missile, space shuttle, space ship, satellite, ocean-going ship, sea carrier, submarine, airplane, and/or silo. The kill vehicle is designed to intercept the warhead and destroy it (or knock it off course) by direct kinetic impact or, by a proximity or contact explosion. It is also possible to destroy a warhead with a laser gun, located at one of the above locations, by directing a laser beam at the warhead to destroy it by heat or ablation. A Space-Based Laser gun is called an ABL (Air Born Laser), while a Ground-Based Laser gun is called a GBL. A laser gun has a servomechanism that requires 5 to 10 seconds to align its beam to the target. In that time period the warhead's trajectory is assumed accurately predicted otherwise the laser beam will miss it. Thus the intercepting force with the warhead can be a kill vehicle, a missile, an airplane, an explosive gun, a laser gun, an electron gun, a particles gun, a fire gun, a jet air gun, a radiation gun, and/or a remote control guided explosive.
The kill vehicle has an on-board computer that mathematically extrapolates and predicts the warhead's trajectory and space coordinates during the kill vehicle travel in space. Extrapolation in time is made using prior space coordinate data collected from the warhead during its travel. This prior data is collected by equipment on-board the kill vehicle, such as radar, video, sensors, IR (infra-red) cameras, and laser beams.
A kill vehicle has on-board equipment which after launch views and acquires or obtains the warhead's space coordinates and calculates the trajectories of both projectiles for the purpose of interception. The kill vehicle has on-board thrusters that adjust its trajectory in space. To obtain an interception, the trajectories of both the kill vehicle and the warhead must cross each other or intersect at an interception point. If the kill vehicle has acquired the warhead's space coordinates and trajectory, but these change, the kill vehicle requires a response time to acquire and change direction in response to the warhead's change of coordinates. This response time to change direction is usually 5-10 seconds and is called a “time-to-go period” (TTG). The kill vehicle's TTG is in part due to its inertia. During the TTG period the kill vehicle's trajectory in space is fixed and cannot be changed. This gives the warhead an advantage, i.e., five-seconds to change its trajectory away from the predicted interception point by at least half of its body dimension, causing the kill vehicle and/or the laser beam to miss it.
A known method of extrapolation based on prior known data is disclosed in U.S. Pat. No. 4,852,129, issued Jul. 25, 1989 to co-inventor Nira Schwartz. The warhead moves relatively slowly in space, allowing accurate prediction of its space coordinates, resulting in approximately a 50% probability of destruction by the kill vehicle. But this is considered a poor probability in lieu of the cost and military war needs. In effort to increase this probability, save warheads from loss, and increase probability of their survival, they were given a mechanical spin called a “coning motion” where the warhead's axis moves with time in space to trace the surface of a virtual cone, or tumbling motion, and/or a combination of these. But kill vehicles were still able to predict the warheads' position with a fair degree of accuracy.